High-Intensity Interval Training Versus Moderate-Intensity Continuous Training for Improving Physical Health in Elderly Women
Question
How does supervised cycle-ergometer HIIT compare with moderate-intensity continuous cycling for body composition, metabolic markers, cardiorespiratory fitness, functional capacity, and quality of life in inactive older women?
Summary
This small randomized supervised cycling study compared 16 weeks of HIIT with moderate continuous cycling in inactive Indonesian women aged 50-60 years with overweight or obesity-range BMI. Both groups improved several body-composition measures, but HIIT produced larger improvements in predicted cardiorespiratory fitness and fasting glucose, while quality-of-life changes were more mixed and bodily pain appeared worse in the HIIT group. The article reports muscle soreness early in training and no cardiac adverse effects, but the sample was small and lifestyle and diet were not monitored.
Methodology
- Twenty-four inactive Indonesian women aged 50-60 years with BMI 25-29.9 kg/m2, randomized to supervised cycling HIIT or MICT.
- 24 participants.
- Bicycle ergometer.
- Work intervals: 4 x 4 minutes at 90-95% estimated age-predicted HRmax.
- Recovery: 3 minutes slow cycling at 50-70% estimated HRmax after each interval.
- Intensity: HR-based, 90-95% age-predicted HRmax during work.
- 38 minutes including 5-minute warm-up and 5-minute cool-down.
- 3 sessions per week.
- 16 weeks.
- Randomized supervised pilot intervention comparing HIIT and MICT before and after 16 weeks of training.
- Body composition, Insulin resistance and fasting glucose, Blood lipids, and Cardiorespiratory fitness were tracked.
Outcomes
Body composition
Both groups significantly reduced body fat percentage, sagittal abdominal diameter, waist circumference, and hip circumference; MICT also had a statistically significant body mass decrease.
Body fat decreased HIIT 1.7% vs MICT 1.2%; waist decreased HIIT 4.2 cm vs MICT 3.3 cm; all p < .05 for listed body composition measures.
Fasting plasma glucose
Only HIIT significantly decreased fasting plasma glucose.
HIIT 6.6 +/- 2.1 to 6.0 +/- 2.2 mmol/L, p < .05; MICT 6.1 +/- 0.8 to 5.8 +/- 0.6 not marked significant.
Cardiorespiratory fitness
HIIT improved predicted VO2max and test termination time more than MICT.
HIIT VO2max 19.7 +/- 11.1 to 27.5 +/- 6.8 mL/kg/min, p = .01, ES = 0.85; MICT 21.6 +/- 11.4 to 24.4 +/- 7.6, ES = 0.19.
Functional capacity
Timed-up-and-go time improved significantly in both groups.
HIIT 6.5 +/- 0.9 to 6.3 +/- 0.8 s; MICT 6.6 +/- 0.9 to 6.5 +/- 0.9 s; both p < .05.
Blood lipids
HIIT produced small practical improvements in total cholesterol and LDL-C, but lipid changes were not statistically significant.
Total cholesterol HIIT -0.4 mmol/L, LDL-C -0.3 mmol/L; p > .05.
Quality of life
MICT improved more SF-36 subscales; HIIT improved role-emotional and mental component summary but bodily pain worsened relative to MICT.
No statistically significant interaction effects for SF-36 subscales; body pain between-group ES = 0.75 favoring MICT.
Insights
- Four-by-four cycling HIIT can improve fitness in inactive older women when supervised and HR-guided.
- Recovery and soreness should be actively managed in older inactive users.
- Quality-of-life response may not track cardiorespiratory fitness improvements.
Limitations
- Small sample size.
- Potential limitations of Bruce protocol fitness assessment.
- Lifestyle, diet, and physical activity outside sessions were not monitored.
- Timing of metabolic blood draws after post-testing was not fully controlled.
- No leg strength or muscle mass measure.
Safety
- Some participants reported muscle soreness after initial sessions.
- No adverse cardiac events were observed.
- Two dropouts were attributed to a separate hip injury and an undisclosed preexisting injury.
- The authors recommend proper screening and doctor contact for high-risk or older populations.